Another Newby question

[kbstenberg]

How much variation in BHN do you see within a single batch of bullets?
If a consistent alloy is used, all the ingots come from the same batch an testing for BHN was done an a random sampling. Say 9 ingots were tested out of a 50lb. batch. An all the numbers came out quite close to each other.
Would the major factor in a different BHN in the cast bullets be from mold temperature when that bullet was cast? Would the length of time the bullet stayed in the mold also have a bearing on how hard it tested at?
I have just started using the Lee tester, an also started testing my bullets for there expansion properties.
Kevin

[Al_sway]

There should be no variation in the BHN, as long as you are air cooling. If you are water dropping then there could be a wide variation.

[Bret4207]

Another thing that can cause variation with a tester is voids in the sample. An unknown void can give a false reading. So if you get a couple with goofy readings.....

[Edubya]

Kevin, our hardness testers are not the end all for testing BHN. There have been numerous test using a variety of testers and different readings were given on the same batch. I don't get more that one BHN difference on a single batch, but I do test 5 or so boolits a couple of days after casting. I imagine that you would have fluctuations if you tested them within hours of casting.

EW